One other thing to try is to find a detail that you want to be medium gray in your image and meter on it. You will likely need to move in to that detail since I don't think that any of your cameras have spot metering, but that won't make any difference. Say you have a tree that is the right color of gray, just walk up toward it, making sure that you don't shade it with your body, and meter on the tree. From that you should be able to get a pretty accurate exposure. You can also use that reading to get an idea of how much to adjust for future exposures, so you don't have to repeat the exercise.
In any case, I would recommend some bracketing. If you are shooting according to the tree, you run the risk of blowing out the snow, even if you have the "correct" exposure, so if I did it that way, I would bracket a couple of shots with less exposure. If I were to just meter the whole scene with the camera, I would do as Rich says.